Data storage systems create snapshots of data objects at various times for a variety of purposes, including backing-up data, providing data recovery, improving application availability, and reducing data management costs, among others. Such snapshots record states of data storage systems by creating point-in-time (PIT) copies of data objects (e.g., data volumes), each of which is organized with associated metadata in a logical address space. Such data volumes include one or more extents of storage space within the logical address space, and the respective extents include multiple data blocks or pages of the same size or different sizes.